Process of manufacturing an electron transport material

ABSTRACT

A process of dissolving 
     
       
         
         
             
             
         
       
     
     in a solvent to produce a first mixture. To the first mixture a reagent is added to produce a second mixture. A H—N—R′—R″ is then added to the second mixture to produce a third mixture. The third mixture is then refluxed to produce

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Non-Provisional application which claims thebenefit of and priority to U.S. Provisional Application Ser. No.62/235,844 filed Oct. 1, 2015, entitled “Process of Manufacturing anElectron Transport Material,” which is hereby incorporated by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

None.

FIELD OF THE INVENTION

This invention relates to a method of manufacturing an interfacialmaterial used in organic bulk heterojunction devices.

BACKGROUND OF THE INVENTION

Solar energy using photovoltaic effect requires active semiconductingmaterials to convert light into electricity. Currently, solar cellsbased on silicon are the dominating technology due to their highconversion efficiency. Recently, solar cells based on organic materialsshowed interesting features, especially on the potential of low cost inmaterials and processing. Judging from the recent success in organiclight emitting diodes based on a reverse effect of photovoltaic effect,organic solar cells are very promising.

Polymeric solar cells are promising approach to photovoltaicapplications as they are cost-effective, flexible, lightweight andpotentially disposable. [6,6]-phenyl-C₆₀-butyric acid-2-hydroxyethylester has been found to be capable of being used in organicphotovoltaics, however it lacks in exhibiting high short-circuit currentdensity and fill factor. There exists a need to produce a polarfullerene derivative yielding high photovoltaic performances byexhibiting higher short-circuit current density and fill factor.

BRIEF SUMMARY OF THE DISCLOSURE

A process of dissolving

in a solvent to produce a first mixture. To the first mixture a reagentis added to produce a second mixture. A H—N—R′-R″ is then added to thesecond mixture to produce a third mixture. The third mixture is thenrefluxed to produce

Another process is taught of dissolving [6,6]-phenyl-C₆₀-butyric acidmethyl ester in 1,2-dichlorobenzene, under an oxygen free environment,to produce a first mixture. Dibutyltin(IV) oxide can then be added tothe first mixture to produce a second mixture. To the second mixtureethylenediamine can be added to produce a third mixture. The thirdmixture can then be refluxed to produce a[6,6]-phenyl-C₆₀-butyric-N-(2-aminoethyl)acetamide.

Another process can be taught of dissolving [6,6]-phenyl-C₆₀-butyricacid methyl ester in 1,2-dichlorobenzene, under an oxygen freeenvironment, to produce a first mixture. Dibutyltin(IV) oxide can thenbe added to the first mixture to produce a second mixture. To the secondmixture 1-ethanol-2-amine can be added to produce a third mixture. Thethird mixture can then be refluxed to produce a[6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide.

An electron transport material is also taught comprising of either[6,6]-phenyl-C₆₀-butyric-N-(2-aminoethyl)acetamide, or [6,6]-phenyl-C₆₀-butyric-N-(2-hydroxy ethyl)acetamide.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention and benefitsthereof may be acquired by referring to the follow description taken inconjunction with the accompanying drawings in which:

FIG. 1 depicts the process to produce

FIG. 2 depicts the [6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide¹H NMR spectrum.

FIG. 3 depicts the [6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide¹H—¹H correlation spectrum.

FIG. 4 depicts the [6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide¹H—¹³C heteronuclear single-quantum correlation spectrum overlaid withthe ¹H—¹³C heteronuclear multiple-bond correlation spectrum.

DETAILED DESCRIPTION

Turning now to the detailed description of the preferred arrangement orarrangements of the present invention, it should be understood that theinventive features and concepts may be manifested in other arrangementsand that the scope of the invention is not limited to the embodimentsdescribed or illustrated. The scope of the invention is intended only tobe limited by the scope of the claims that follow.

The present embodiment describes a process to produce

As shown in FIG. 1, the process begins by dissolving

in a solvent to produce a first mixture, step 101. To the first mixturea reagent is added to produce a second mixture, step 103. A H—N—R′—R″ isthen added to the second mixture to produce a third mixture, step 105.The third mixture is then refluxed to produce

step 107.

In one embodiment R can be selected from groups such as H, CH₃,carbonate, SH, F, Cl, Br, I, CN, OH, Si, NH₂, and any alkyl chains

As described above step 101 begins by dissolving

in a solvent to produce a first mixture. Any conventionally knownsolvent capable of dissolving

can be used. In one example the solvent used can be any conventionallyknown organic solvent. Examples of organic solvents can includedichlorobenzene, chlorobenzene, xylene, toluene, chloroform,tetrahydronaphthalene, carbon disulfide, dichloromethane, ethyl acetate,ethanol, hexane, cyclohexane, tetrahydrofuran and isopropanol. Anyconventionally known method of dissolving

in the solvent can be used. These methods include mixing, stirring andheating and sonicating.

In step 103, a reagent can be added to the first mixture to produce asecond mixture. These reagents used can be any agent able to cleave Rfrom

The addition of the reagent to the first mixture is ideally done in anoxygen-free environment but not required. In one embodiment the agent isa metal oxide. In another embodiment the reagent is an acid. In anotherembodiment the reagent is dibutyltin (IV) oxide, hydrochloric acid,sulfuric acid, nitric acid, or acetic acid. In another embodiment acombination of the mentioned reagents is used.

In step 105, a H—N—R′—R″ can be added to the second mixture to produce athird mixture. In one embodiment R′ is selected from —(CH₂)_(n)—, wheren is any integer of one or greater. Also R″ is selected from either N,O, S, C, or B. In other embodiment R″ can be alkyl chains or substitutedalkyl chains. Examples of substitutions for the substituted alkyl chainsinclude halogens, NH₂, Br, OH, Si, or S. In one example R′ is an ethylgroup of the structure —(CH2CH2)— and R″ can be selected from NH₂ or OH.

In step 107, the third mixture is then refluxed to produce

Dependent upon the selection of H—N—R′R″

could be [6,6]-phenyl-C₆₀-butyric-N-(2-aminoethyl)acetamide, or[6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide.

The molar ratios of the chemical used can be.

Chemical Molar Ratio

  1 ± 0.9 Reagent 200 ± 199 H—R′—R″ 200 ± 199

The following examples of certain embodiments of the invention aregiven. Each example is provided by way of explanation of the invention,one of many embodiments of the invention, and the following examplesshould not be read to limit, or define, the scope of the invention.

EXAMPLE 1

[6,6]-Phenyl-C₆₀-butyric acid methyl ester (0.25 g, 0.274 mmol) wasdissolved in 1,2-dichlorobenzene (12 mL) in a dry schlenk flask underargon. Dibutyltin(IV) oxide (0.068 g, 0.274 mmol) was added in oneportion. Ethylenediamine (0.2 mL) was added in one portion and thesolution heated to 180 ° C. for two hours. The brown precipitate wasfiltered, sonicated in methanol and centrifuged. The solid[6,6]-phenyl-C₆₀-butyric-N-(2-aminoethyl)acetamide was sonicated inacetone and centrifuged to yield the product as a brown solid (0.21 g,84% yield).

EXAMPLE 2

[6,6]-Phenyl-C₆₀-butyric acid methyl ester (2.0 g, 2.2 mmol) wasdissolved in dry 1,2-dichlorobenzene (25 mL) in a dry Schlenk flaskunder argon. Dibutyltin(IV) oxide (0.548 g, 22 mmol) was added in oneportion. Ethanolamine (0.134 g, 2.2 mmol) was added via syringe and thesolution was heated to reflux for 18 hours. The solution was cooled andpoured directly onto a column packed with toluene. The solvent wasgradually changed to a 4:1 toluene/tetrahydrofuran mix and pure[6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide was isolated as abrown powder (0.12 g, 24% yield).

NMR Spectroscopy

Nuclear magnetic resonance spectroscopy was performed on a 400 NMRspectrometer, operating at 400.16 MHz for ¹H.

FIG. 2 depicts the [6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide¹H NMR spectrum.

FIG. 3 depicts the [6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide¹H-¹H correlation spectrum.

FIG. 4 depicts the [6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide¹H-¹³C heteronuclear single-quantum correlation spectrum overlaid withthe ¹H-¹³C heteronuclear multiple-bond correlation spectrum.

Performance Data

Average performance data of different organic photovoltaic devices usingdifferent electron transport layers were done.

Open-circuit Short-circuit voltage current Fill Power Electronic Vocdensity Jsc Factor Conversion Transport layer (V) in mA/cm² % Efficiency% ZnO 0.785 15.9 65.9 8.24 ZnO:[6,6]-phenyl- 0.756 16.0 57.6 6.99C₆₀-butyric-N- (2-hydroxyethyl)- acetamide

In closing, it should be noted that the discussion of any reference isnot an admission that it is prior art to the present invention,especially any reference that may have a publication date after thepriority date of this application. At the same time, each and everyclaim below is hereby incorporated into this detailed description orspecification as an additional embodiment of the present invention.

Although the systems and processes described herein have been describedin detail, it should be understood that various changes, substitutions,and alterations can be made without departing from the spirit and scopeof the invention as defined by the following claims. Those skilled inthe art may be able to study the preferred embodiments and identifyother ways to practice the invention that are not exactly as describedherein. It is the intent of the inventors that variations andequivalents of the invention are within the scope of the claims whilethe description, abstract and drawings are not to be used to limit thescope of the invention. The invention is specifically intended to be asbroad as the claims below and their equivalents.

1. A process comprising: a) dissolving

in a solvent to produce a first mixture; b) adding a reagent to thefirst mixture to produce a second mixture; c) adding a H—N—R′-R″ to thesecond mixture to produce a third mixture; d) refluxing the thirdmixture to produce


2. The process of claim 1, wherein

is [6,6]-phenyl-C₆₀-butyric acid methyl ester.
 3. The process of claim1, R are selected from the group consisting of: H, CH₃, carbonate, SH,F, Cl, Br, I, CN, OH, Si, NH₂, substituted alkyl chains andunsubstituted alkyl chains.
 4. The process of claim 1, wherein thesolvent is an organic solvent.
 5. The process of claim 1, wherein thesolvent is selected from the group consisting of: dichlorobenzene,chlorobenzene, xylene, toluene, chloroform, tetrahydronaphthalene,carbon disulfide, dichloromethane, ethyl acetate, ethanol, hexane,cyclohexane, tetrahydrofuran and isopropanol.
 6. The process of claim 1,wherein the reagent selected is able to cleave R from


7. The process of claim 1, wherein the reagent is a metal oxide.
 8. Theprocess of claim 1, wherein the reagent is selected from the groupconsisting of: dibutyltin (IV) oxide, hydrochloric acid, sulfuric acid,nitric acid, acetic acid and combinations thereof.
 9. The process ofclaim 1, wherein R′ is —(CH₂)_(n)—, wherein n is any integer of one orgreater.
 10. The process of claim 1, wherein R″ are selected from thegroup consisting of: N, O, S, C, B, unsubstituted alkyl chains andsubstituted alkyl chains.
 11. The process of claim 9, wherein thesubstitutions for the substituted alkyl chains are selected from thegroup consisting of: halogens, NH₂, Br, OH, Si, S and combinationsthereof.
 12. The process of claim 1, wherein

is selected from the group consisting of:[6,6]-phenyl-C₆₀-butyric-N-(2-aminoethyl)acetamide, and[6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl) ester.
 13. The process ofclaim 1, wherein

is used as an electron transport material in an organic photovoltaicdevice.
 14. A process comprising: a) dissolving [6,6]-phenyl-C₆₀-butyricacid methyl ester in 1,2-dichlorobenzene, under an oxygen freeenvironment, to produce a first mixture; b) adding dibutyltin(IV) oxideto the first mixture to produce a second mixture; c) addingethylenediamine to the second mixture to produce a third mixture; and d)refluxing the third mixture to produce[6,6]-phenyl-C₆₀-butyric-N-(2-aminoethyl)acetamide.
 15. A processcomprising: a) dissolving [6,6]-phenyl-C₆₀-butyric acid methyl ester in1,2-dichlorobenzene, under an oxygen free environment, to produce afirst mixture; b) adding dibutyltin(IV) oxide to the first mixture toproduce a second mixture; c) adding 1-ethanol-2-amine to the secondmixture to produce a third mixture; and d) refluxing the third mixtureto produce [6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide
 16. Anelectron transport material selected from the group consisting of:[6,6]-phenyl-C₆₀-butyric-N-(2-aminoethyl)acetamide, and[6,6]-phenyl-C₆₀-butyric-N-(2-hydroxyethyl)acetamide.
 17. The electrontransport material of claim 15, wherein the thickness is less than 100nm.